I don't believe the reason for God commanding us not to eat certain things totally has to do with health. I believe its a call to be seprate or holy. We know that a pig is a very dirty animal but there are other creatures that God calls us not to eat that are not really unhealthy. Most of which are found in the sea. I believe its a call by God to be different, to be seprate or holy as He is holy.
Lev. 11:44-47 `For I am the Lord your God. You shall therefore sanctify yourselves, and you shall be holy; for I am holy. Neither shall you defile yourselves with any creeping thing that creeps on the earth. `For I am the Lord who brings you up out of the land of Egypt, to be your God. You shall therefore be holy, for I am holy. `This is the law of the beasts and the birds and every living creature that moves in the waters, and of every creature that creeps on the earth, 'To distinguish between the unclean and the clean, and between the animal that may be eaten and the animal that may not be eaten.' ''
God sets certain standards for a people who are called by His name.
2 Chronicles 7:14 "If My people who are called by My name will humble themselves, and pray and seek My face, and turn from their wicked ways, then I will hear from heaven, and will forgive their sin and heal their land.
It's in these standards that make us different from the world. It's in these standards that we are able to express faith working through love.
If there are no standards then there is no holiness for God calls us to be holy as He is holy.
1 Peter 1:13-16 Therefore gird up the loins of your mind, be sober, and rest your hope fully upon the grace that is to be brought to you at the revelation of Jesus Christ; as obedient children, not conforming yourselves to the former lusts, as in your ignorance; but as He who called you is holy, you also be holy in all your conduct, because it is written, "Be holy, for I am holy.''
Holiness is dertermined by the standard set by God.
2 Timothy 3:1-5 But know this, that in the last days perilous times will come: For men will be lovers of themselves, lovers of money, boasters, proud, blasphemers, disobedient to parents, unthankful, unholy, unloving, unforgiving, slanderers, without self-control, brutal, despisers of good, traitors, headstrong, haughty, lovers of pleasure rather than lovers of God, having a form of godliness but denying its power. And from such people turn away!